Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral context beyond that: it explains that members are a live lens, that version resolution defaults to published but can preview drafts, and that summarized kinds are omitted from members with a members_complete flag. It also clarifies the union formula. No contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is relatively long (~200 words) but every sentence addresses a necessary aspect: core purpose, resolution logic, summarization behavior, alternatives, and usage guidance. It is front-loaded with the primary action and well-structured. While it could be tightened, the length is justified by the tool's complexity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the output schema exists (which would document return fields), the description still covers essential behavioral details: the union formula, summarized kind handling, members_complete flag, and version resolution. It also provides guidance on alternatives and when to use this tool. Nothing an agent needs to invoke it correctly appears missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all three parameters. The description adds no new parameter-specific meaning beyond what the schema provides (e.g., the version behavior is already in the schema). It does add context about summarized kinds, but that is output behavior, not parameter semantics. Per the baseline for high coverage, a score of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly identifies the tool as resolving an app's live member set and specifies the exact output structure ({kind, slug, display_name}). It explicitly contrasts with other tools (e.g., get_app, list_datafiles) by explaining this is a resolved view based on rules, not a stored list. The purpose is unambiguous and distinct from siblings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It states precisely when to use the tool: 'Use this to see or verify what an app contains.' It also gives explicit guidance for summarized kinds, directing the agent to call the kind's own list tool with a slug_prefix, and notes this tool never pages a whole collection. This provides clear alternatives and exclusion criteria.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.